"use client"

import { useState, useEffect } from "react"
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
import { Button } from "@/components/ui/button"
import { Skeleton } from "@/components/ui/skeleton"
import { AlertCircle, Package, ArrowRight, ShoppingCart } from "lucide-react"
import { clientFetch } from "@/lib/api"
import Image from "next/image"
import Link from "next/link"

interface LowStockWidgetProps {
    settings?: {
        threshold?: number
        itemCount?: number
    }
}

interface LowStockProduct {
    id: string
    name: string
    currentStock: number
    unitType: string
    image?: string
}

export default function LowStockWidget({ settings }: LowStockWidgetProps) {
    const threshold = settings?.threshold || 5
    const itemCount = settings?.itemCount || 5
    const [products, setProducts] = useState<LowStockProduct[]>([])
    const [isLoading, setIsLoading] = useState(true)
    const [error, setError] = useState<string | null>(null)

    const fetchLowStock = async () => {
        try {
            setIsLoading(true)
            setError(null)
            // Implementation: We'll use the product-performance API and filter locally
            // or a dedicated stock-report API if available. 
            // For now, let's use the product-performance endpoint which has stock info.
            const response = await clientFetch('/analytics/product-performance')

            const lowStockProducts = response
                .filter((p: any) => p.currentStock <= threshold)
                .sort((a: any, b: any) => a.currentStock - b.currentStock)
                .slice(0, itemCount)
                .map((p: any) => ({
                    id: p.productId,
                    name: p.name,
                    currentStock: p.currentStock,
                    unitType: p.unitType,
                    image: p.image
                }))

            setProducts(lowStockProducts)
        } catch (err) {
            console.error("Error fetching low stock data:", err)
            setError("Failed to load inventory data")
        } finally {
            setIsLoading(false)
        }
    }

    useEffect(() => {
        fetchLowStock()
    }, [threshold, itemCount])

    if (isLoading) {
        return (
            <Card className="border-border/40 bg-background/50 backdrop-blur-sm">
                <CardHeader className="pb-2">
                    <Skeleton className="h-5 w-32 mb-1" />
                    <Skeleton className="h-4 w-48" />
                </CardHeader>
                <CardContent className="space-y-4">
                    {[1, 2, 3].map((i) => (
                        <div key={i} className="flex items-center gap-4">
                            <Skeleton className="h-12 w-12 rounded-lg" />
                            <div className="space-y-2 flex-1">
                                <Skeleton className="h-4 w-3/4" />
                                <Skeleton className="h-3 w-1/4" />
                            </div>
                        </div>
                    ))}
                </CardContent>
            </Card>
        )
    }

    return (
        <Card className="border-border/40 bg-background/50 backdrop-blur-sm overflow-hidden flex flex-col h-full">
            <CardHeader className="flex flex-row items-center justify-between pb-2">
                <div className="space-y-1">
                    <CardTitle className="flex items-center gap-2">
                        <AlertCircle className="h-5 w-5 text-amber-500" />
                        Low Stock Alerts
                    </CardTitle>
                    <CardDescription>
                        Inventory checks (Threshold: {threshold})
                    </CardDescription>
                </div>
                <Link href="/dashboard/stock">
                    <Button variant="ghost" size="sm" className="h-8 gap-1.5 text-xs">
                        Manage
                        <ArrowRight className="h-3 w-3" />
                    </Button>
                </Link>
            </CardHeader>
            <CardContent className="pt-4 flex-grow">
                {error ? (
                    <div className="flex flex-col items-center justify-center py-10 text-center">
                        <Package className="h-10 w-10 text-muted-foreground/20 mb-3" />
                        <p className="text-sm text-muted-foreground">{error}</p>
                    </div>
                ) : products.length === 0 ? (
                    <div className="flex flex-col items-center justify-center py-12 text-center">
                        <div className="h-12 w-12 rounded-full bg-green-500/10 flex items-center justify-center mb-4">
                            <Package className="h-6 w-6 text-green-500" />
                        </div>
                        <h3 className="font-medium">All systems go</h3>
                        <p className="text-sm text-muted-foreground mt-1 max-w-xs">
                            No products currently under your threshold of {threshold} units.
                        </p>
                    </div>
                ) : (
                    <div className="space-y-1">
                        {products.map((product) => (
                            <div
                                key={product.id}
                                className="flex items-center gap-4 p-3 rounded-xl hover:bg-muted/50 transition-colors group"
                            >
                                <div className="h-12 w-12 relative rounded-lg border bg-muted overflow-hidden flex-shrink-0">
                                    {product.image ? (
                                        <Image
                                            src={`/api/products/${product.id}/image`}
                                            alt={product.name}
                                            fill
                                            className="object-cover group-hover:scale-110 transition-transform"
                                        />
                                    ) : (
                                        <div className="h-full w-full flex items-center justify-center">
                                            <ShoppingCart className="h-5 w-5 text-muted-foreground/40" />
                                        </div>
                                    )}
                                </div>
                                <div className="flex-grow min-w-0">
                                    <h4 className="font-semibold text-sm truncate">{product.name}</h4>
                                    <div className="flex items-center gap-1.5 mt-0.5">
                                        <span className="text-[10px] uppercase font-mono tracking-wider text-muted-foreground bg-muted-foreground/10 px-1.5 py-0.5 rounded">
                                            ID: {product.id.slice(-6)}
                                        </span>
                                    </div>
                                </div>
                                <div className="text-right">
                                    <div className={`text-sm font-bold ${product.currentStock === 0 ? 'text-destructive' : 'text-amber-500'}`}>
                                        {product.currentStock} {product.unitType}
                                    </div>
                                    <div className="text-[10px] text-muted-foreground font-medium uppercase tracking-tighter">Remaining</div>
                                </div>
                            </div>
                        ))}
                    </div>
                )}
            </CardContent>
        </Card>
    )
}